This invention relates to a circuit arrangement including a differential transistor circuit.
As a typical one of such circuit arrangements, a comparator is known wherein an output signal is produced when an input signal level exceeds a predetermined threshold voltage. In this comparator, the threshold voltage is determined by a difference between base voltages of both transistors of the differential transistor circuit. The threshold voltage is kept constant in the conventional comparator. However, it has been found out that such a constant threshold voltage often gives rise to inconvenience in practical use.